CHICAGO (CBS) — Gov. JB Pritzker and Illinois Public Health Director Dr. Ngozi Ezike are urging people to take extra precautions against COVID-19 if they are planning to attend New Year’s Eve parties, to avoid further spread of the virus amid the latest surge of the pandemic.

“Let’s be clear, every single event being held during this holiday season will have one or two uninvited unwanted guests: Delta and/or Omicron,” Dr. Ezike said Monday afternoon during a COVID-19 briefing at the Thompson Center.

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Ezike and Pritzker said anyone planning to attend any New Year’s Eve gatherings should get a COVID-19 vaccine or booster shot, wear a mask, and get tested for the virus beforehand.

“Omicron and Delta are coming to your party. So you need to think twice about how many people will be gathered together; keeping social distancing if you’re at a party; and if you can’t, leave,” Pritzker said.

Ezike said she recognizes, even with cases on the rise again, many people will choose to get together for parties on New Year’s Eve, so she wants people to make sure they do everything possible to protect themselves, by wearing masks in public, observing social distancing as much as possible, and getting vaccinated.

“Obviously, you are safer if you are not in that large, crowded gathering. That’s probably the safest,” Ezike said. “The next thing would be that if you’re going to go to a gathering, that there are not as many people. The next thing is that if you’re going to be in a gathering there are a lot of people, that you keep your mask on the entire time, and you put on a high-quality mask. That absolutely can be very helpful if people are wearing masks.”

Ezike warned that Illinois is in the midst of the fastest surge of COVID-19 cases since the start of the pandemic.

“We’re absolutely seeing the highest surge in cases from across the entire pandemic for the last two years,” she said, noting Illinois set a new daily COVID-19 case record last week, with 21,131 new cases reported on Friday, the most ever reported in a single day in Illinois during the pandemic.

As of Monday, Illinois is averaging 14,535 new cases of COVID-19 per day over the past week, up 227% since the beginning of the month.

However, testing for COVID-19 also has surged this month, so the state’s average positivity rate still remains lower than the peaks of the first two waves of the pandemic in 2020. The state’s average case positivity rate — the percentage of new cases among total tests for the virus — stands at 7.8%, up from 4.7% at the start of the month, after reaching as high as 13.2% during the fall surge in 2020, and as high as 20% during the first wave of the pandemic in May 2020. Illinois is averaging 186,774 coronavirus tests per day over the past week, an 87% increase since the beginning of December.

Since the start of the pandemic, Illinois has reported 2,077,260 total cases of COVID-19, including 27,588 deaths.

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Hospitalizations and deaths from COVID-19 also are on the rise. As of Sunday night, 4,755 people were hospitalized with COVID-19 in Illinois, a 93% increase since the start of the month, but still below the peak of 6,175 hospitalizations on Nov. 20, 2020. Illinois is averaging 51 COVID deaths per day over the past week, up 143% since Dec. 1. The peak was 155 deaths per day in early December 2020.

“The vast, vast majority of cases, hospitalizations, and deaths are among those who are not vaccinated,” Dr. Ezike said.

The latest surge in cases comes as the Omicron variant has become the most dominant strain of the virus in the U.S., accounting for 73% of all new cases last week.

In light of the latest surge in cases, Pritzker said the state will be increasing the number of available booster and vaccination clinics across the state to meet the increasing demand for shots. The Illinois Department of Public Health also will be helping local health departments increase staffing and testing capacity; and adding 1,100 people to regional vaccination sites, allowing the state to provide tens of thousands more shots each day.

Also, starting next week, the state’s free community-based testing sites will begin operating six days a week, up from four days a week, to help meet the increased demand for tests.

“I’m going to continue to do everything possible to protect all of the people of our state, whatever your vaccination status, but what kind of year 2022 turns out to be depends on all of us doing what is best for all of us,” Pritzker said.

The governor also urged people who have yet to be vaccinated to get their shots, to avoid overwhelming hospitals with COVID-19 patients.

“If you are unvaccinated and you get very sick, you’ll be filling a bed that would have been available for your ailing spouse, or your parent, or your child, or someone else’s child; someone with cancer, or a heart attack, or seriously injured in a car accident,” he said. “If you are choosing not to be vaccinated for some non-medical reason, please change your mind.”

Ezike said, while people who have been fully vaccinated can still get COVID-19, she said vaccines can prevent severe illness and death.

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“Admittedly, nothing is 100%. No vaccine is 100%, but if you can significantly drastically reduce your chance of being hospitalized or dying, why wouldn’t you avail yourself of this opportunity?” she said.

CBS 2 Chicago Staff